The present invention relates to fastening devices and more particularly to a device for fastening the barrel of a gas operated soldering gun with improved characteristics.
Gas operated soldering guns have been widely used in recent years. It has the advantages of quick heating or stopping, high safety, and convenience. The body of a conventional gas operated soldering gun 3 having substantially the same construction as the invention is shown in phantom lines in FIG. 5. The gun 3 comprises a forward barrel 2 and a rearward combustion chamber 32 with flammable gas contained therein. A nozzle 22 is threadably secured to a forward end 21 of the barrel 2. A tip 23 is threadably secured to a forward end of the nozzle 22. A spout 31, extended forwardly from the combustion chamber 32, is connectable to the barrel 2 by performing one of the following techniques.
As shown in FIG. 1, a first technique involves a coupling of the spout 31 and the barrel 2 by means of mated threaded sections 6. As shown in FIG. 2, a second technique involves a coupling of the spout 31 and the barrel 2 by means of two or more projections 4 urged against the outer surface of the spout 31 in which the projections 4 are formed by punching on the outer surface of the barrel 2. As shown in FIG. 3, a third technique involves a coupling of the spout 31 and the barrel 2 by forming a threaded hole 5 through the barrel 2 so that a screw 51 can be driven into the hole 5 to fasten the outer barrel 2 to the inner spout 31. A fourth technique involves a coupling of the spout 31 and the barrel 2 by shaping the interior of the barrel 2 differently from the outer surface of the spout 31 so that a rotation of the barrel 2 about the spout 31 or vice versa can fasten them together by snapping.
However, the prior art suffered from several disadvantages with respect to safety and convenience in practice. For example, the coupling by means of the threaded sections 6 as illustrated in FIG. 1 is time consuming in assembly or disassembly of the spout 31 and the barrel 2. As to the projections 4 illustrated in FIG. 2, despite of the benefit of quick assembly it still has the drawbacks of uncontrolled allowances of the projections 4, resulting in a failure of conforming to the spout 31, and disengagement of the spout 31 from the barrel 2 due to long time wear of hard contact between the projections 4 and the spout 31. Such drawback of disengagement of the spout 31 from the barrel 2 is also occurred in the fourth technique. As to the threaded coupling illustrated in FIG. 3, despite of the benefit of reliable fastening it also has drawbacks of requiring a tool (e.g., screw driver) to fasten the screw 51 in assembly or unfasten the screw 51 in disassembly. This is quite time consuming and tedious. Moreover, in removing the heated barrel 2 during operation the user has to use one hand to hold the gun 3 and the other hand to remove the barrel 2. This is quite inconvenient and it is possible of hurting the hand by the hot barrel if enough care is not taken. This is not a safe technique. Thus, the need for improvement still exists.
It is an object of the present invention to provide a device for fastening a barrel of a gas operated soldering gun to a spout thereof. The fastening device has advantages of quick assembly or disassembly of the barrel and the spout, increased soldering efficiency, and high safety.
To achieve the above and other objects, the present invention provides a device for fastening a barrel of a gas operated soldering gun to a spout of a combustion chamber thereof. The fastening device comprises a cavity in a rear end of the barrel, a resilient clip disposed in the cavity, and a plurality of latched pieces on the clip, the latched pieces being disposed inside the clip. The spout can be fastened in the barrel by clinging the barrel to the spout as the latched pieces exert a strong, resilient force onto the spout.
The above and other objects, features and advantages of the present invention will become apparent from the following detailed description taken with the accompanying drawings.